Chives are perennial plants that grow in clumps and may reach 2' in height, but are generally kept cut back so the grass-like leaves can be used in the kitchen. They prefer growing in cool weather so yours may be getting too much summer sunshine or they are stressed by the heat. Grow your chives in a partly sunny or lightly shaded garden site, in moist, fairly rich soil. Harvest by cutting the amount of foliage you need with a pair of scissors. The plants will remain evergreen in mild winter areas but will go dormant if winter weather is cold. If your plants become dormant, the roots will remain alive and will produce new foliage the following spring. Some gardeners allow the plants to develop flower stalks which produce a globe-like cluster of purple flowers. Try moving your chives to a site with morning sun but shade from hot afternoon sun and they may perk up for you. Hope so!